Artificial foot and ankle-joint.



' E.- -MUELLER- l ARTIFICIAL FOOT AND'ANKLE JOINT.

APPLIoATIox HLM-5m17.190s.'

Patented July 2 SHEETS- Any FIGA. v

A E. MUBLLER. ARTIFICIAL FOOTjJAND rANKLE JOINT.

nrLIoA'rIolrILnn s111112?, 1909.

Patented July 12, 1910.

B BHEBTB-SBBET 2.

ENGELBERT yIVJIU'ELLER, 0F RESERVE TOWNSHIP, ALLEGI-IENY COUNTY,`

PENNSYLVANIA.

ARTIFICIAL FOOT AND ANKLE-JOINT.

' Specification of Letters Patent.

Patented July 12, 1910.

Application filed September 7, 19Q9. Serial No. 516,489.

'.To' all who/m it may concern:

my present invention Yis employed. parts are for purpose of illustration shown Be it known that I, ENGELBERT MUELLER,

residing at Reserve township, in the county.`

of Allegheny and State of Pennsylvania, a citizen of the United States, have invented or discovered certain new and useful Im- Joints, of which improvement the following is a specification.

My invention relates to improvements in the construction of artificial limbs and the objects oit my invention are simplicity of structure, facility of separation of parts, and durability.

ln thel accompanying drawings which -forno. part of this specification Figure l shows in perspective view yan artificial foot and lower leg in the construction of whiplh l1 e detached .the one from the other. Fig. 2 is a. side elevation of the foot and lower leg assembled. Fig. 3 is an end view in perspective of a foot alone. Fig. l: shows in elevation, and in two views, the hinge knuckles detached 'from one another.

larts which are repeated in the several lignres bear the saine reference numerals in each case.

l shall iirst describe the hinge-joint which forms part of my ilivenlimi; l shall describe it. in its application lo an ankle joint of an artificial leg,r but it will be understood that lit is applicable not to the formation of that particular joint only, but to other joints as well. in artificial limb construction.

' The joint itseltis made up of three members, two hinge-kmu-kles which are bolted to the two artilicial limb parts which are to be articulated and a. hinge-pin which unites them. These two knuckle parts are shown at l and 2 in the drawings, and the hingepin is shown at Fach ot these hinge knuckles l and Q bolted lo n limb part. and each knuckle |n-"olrudes 'to-engage its fellow knuckle and lo besecured to it by the knuckle-pin. to Aform the joint. j

ln the articulated toot and ankle taken t'or purpose oi illustration, it. will be seen that the hinge-knuckle l is carried on and forms the head of a bolt YIl whose shank protrudcs into a recess 5 in the leg portion of this artificial toot, that the protruding shank is'threaded and receives a nuty 6 to secure the whole. rl`he hinge-knuckle 2 is bolted to the Aposes of replacement and repair.

foot member by a bolt 7 of which it forms the head and this bolt is secured by the nut 8 which is conveniently arranged to seat in a countersunk recess in the sole of the foot` .3 will in good construction be made large,-

to aiiord an extended bearing surface, and itis preferably hollow as shown, and is made hollow for the sake of lightness. Being hollow, l find it convenient. to utilize the hollow space within it as an oil4 cup. To this end an oil duct- 9 isdrilled through the wall of this hollow pin, to admit a liow of oil to the bearing surface of the joint. Some absorbent substance saturatedwith oil inserted within the hollow pin will thus keep the joint lubricated. For the sake of strength, the knuckles and pin are preferably made of steel, and it will be found advantageous, contributing to the durability of the structure, to place within the hole in the hinge-block 2, a bushing 10 of a soft metal` such as brass.

A further feature of this hinge-joint construction is the building out `of the hingebloek 2 to form a shoulder l1, which, as the parts swing, will abut against the face of the web 12 of the clevis, and such abutting will limit the pivotal movement. Thisis done, as the drawings show, so that the rearwardswing of the foot from its horizontal position is permitted, but the forward swing beyond a certain point. is absolutely stopped.

The hinge-joint as thus far described is so applied and assembled with the limb members which it articulates, that the limb mem. bers while securely held together in service may readily be detached from one another and the-,hinge-parts themselves be readily detached trom the limb members for pur- To the end that the hinge parts may readily be de.-

t-ached, each forms the head of a single boltV l ment.

that the articulated limb members may be separated without taking the structure apart, thehinge-pin is removable. But, to guard against its accidental removal and to secure it when the arts are assembled, a

f particular construction is employed. One

nuckle of the hinge, preferably the clevis member 1, is so mounted and carried in its limb ,member that by tightening the bolt of whichthe knuckle froms the head, the hin e-pin, when in place within the knuckle is c amped against the body of the limb member, meure against accidental displace- A loosening of the bolt, on the other hand, leaves the pin free to be withdrawn and reapplied for purposes of separating and assembling.

In order that the structure may be compact, and .that the hinge-pin may be the more securely held against the body of the limb member, a groove, 16, is preferably formed in the limb member to receive and frictionally hold the pin. It will be understood that when the parts are assembled for service the pin will preferably have no rotary movement upon the surface of groove 16, but will be stationary therein, and the knuckle 2 will swing upon it. And from this it will be understood that the lubrical tion afforded by the oil duct 9 in the pin is over that portion of the outer surface of the pin upon which the knuckle 2 has bearing.

' As the joint turns, the pin will turn against 13 (which or the surface' of the adjacent limb member, and for the sake of compactness the pin rests in a groove formed in' the surface of that member also. For durability, the wearing surface of this latter groove may be faced with rawshide or other suitable material.

The pivotal movement of the limb mem- .bers as thus far described is limited only by the positive stop within `the joint itself; but

Vthe permissible movement is not left free and uncontrolled. Movement in one direction is limited by the positive stop already described; movement in the other direction is cushioned, cpreferably by a spring such as ."cased in buckskinll engaging opposite porthis sprin upon a cushion 14 carried tions of the twolimbvmembers, and this -spring 1s compressed as the jointed parts swing. In the foot construction illustrated,

of Achilles. But motion in the opposite direction :too is preferably controlled and cushioned, to the end that as the. joint turns and approaches a dead stop the movement willfbe checked andthe stop will be 'less abrupt... I have shown alternative means for alfordin ,such cushioning. In Fig. 1

opposite sur aces of the jointed limb members are arranged to eng y one of said surfaces, slightly in advance of the engageinarily will be a coiled spring 13 lies on the posterior side of` the ankle Joint, approximately at the tendon" I"tongue 20.

e one anotherl .soft wood as willow, I obtain a strengthen ing at this oint, (Fig. l) by the insertion of a block o hard wood, l5 inthe solid body cie construction illustrated in Fig. 2, the spring 14:a is backed by a block of hard wood,15. -f f My invention in its further details has to do with the construction of an artificial foot.

An artificial foot is commonly made of an upper body of soft wood and a sole body 0i felt, and extending longitudinally on the 'sole and over the ball of the foot is a strip of elastic, held tense to afford a desired elasticity to that part of the structure.

Myinvention, o far as concerns the foot construction, consists in inserting between yof the leg member; to like edect, in the spethe upper and the s'ole bodies such as I have described, a stri or tongue of relatively tough and tenaclous material, such as hard wood, to add materially to the Vlife and strength of the Whole structure, this strip or tongue of tenacious material is preferably dovetailed into the bodies of materialv whichl forms the upper and sole parts of the foot. In employing the ankle joint such as I have described I cause the bolt 7 of the knuckle which the foot member carries to be extended through this tongue of hard wood or likeA substance, and thus the tongue of hard wodd contributes to the serviceability of the joint.

In the drawings, 18 represents the upper part of the foot, which will referably be made of soft wood, such as w' ow, 19v is the sole part of the foot, ordinarily made of felt, and 2() is the tongue of'hard wood which, as the drawings show, is dovetailed in the part 18 above and the part 19 below. AIn thisl 'lis foot construction the socket in the foot mem- Y ber for the springs 13l and 1li will preferablyV be carried downto the hard wood `Another bolt, 22, extending:

through the component parts 'of the foot at the anterior end, binds the whole more se-V curely together. The form of the bolt which I have found best adapted in this construction consists of a sleeve provided Awith an angular countersunk head'23, which extends,

through a hole in the foot made to receive it. The sleeve is threaded Within at its lower end; and, engaging this thread portion, is a screw 24C, w ose head 1scounterprovided with surfaces which 1 and the parte of the bolt are drawn together to iirmly unite the parts.

vThis bolt 22 extends through. the tongue 2U aswellas througl'i the body of the upper part of the foot and sole v adds to the strength of thc structure as a whole. The bolt 2v2 may com-'enwntly be employed to engage one end of lthe elastic band 2l (the opposite forward end thereol" being secured to the sole body) and hold the band securein tense pos1t1on.

l claim herein as my i-ni-'tiitioiiz l. in a` joint l'or an arlilieial limb, the i combination of two limb membr-rs prt'ivided with correspondii1pl hinge-knuckles, and a hinge-pin removably engaging lsaid linurlth and completing` the joint, and 'when in posi-- tion extending' adjacent to the surface of one of said ljmb members, and means lor securing said hinge-pin against said surface, substantially as described.

2. ln a joint for an artificial limb the eonil'iination ot' a limb member, a. bolt whose shank extends through they body of said limb member and n-l'mse head protrndes from one surface thereof, such protruding' bead being .shaped lo torni a liingg'e-lnueltle, a hingepin removable in said hinge-knuckle, and when in place therein extendinpl 'adjacent-'to .the aforesaid surface of the limb member,

a nut upon the shank of said bolt securing said bolt in the limb member' and holding said. hinge-pin aga-inst the aforesaid snrface, substantially described.

3. In a jointilor an artificial limb, the rombii'iation. of two limb members, art-icul11[ed together by a. joint, the members of said joint [i1-fingy provided withv abutting surfaces which :limit the hinge nim-ement in one direction. :l-1e said limb members being yieldingly engage one another as the abutting surfaces of the joint. approach one another. "d

l. 'liu an ankle joint for an artificial le r the combination of a. solid leg inenfiber and a foot meml'mr articulated together by a. joint. which limits the forward swing of the tool: member upon the leg member, the said foot andlep; members being provided with. surfaiwzs on tl 'whichyieldingly engage one another as the forwardly swinging foot approaches the lin'litf oi its jointed movement, the said leg member being reinforced by a block of rela.- tively hard and tenacious material 'at the 1e anterior side of said joint.

l l 1 l l i l ball of the said yielding' engagement is made with the 'foot member, such reinforcing' block being sunk. in the Solid body or' said leg member, substantially as described.

:3. A11 artificial foot comprising a sole bmly, an upper body and a strip extending longitudinally between, to which said sole and upper bodies are dovetailed, substantially as described.-

13. An artificial foot comprising a sole body olf telt, an upper body ol. soft wood and :111 interposed tongue of lrard'wood upon wl 1ich said solo and up 3er bodies are dovetajled, s1'1bstantially as cescribed.

11i-K11 artificial foot. comprising a-.Sole body, an upper body and an interposed uniting strip of relatively hard and'tenaoious material, said :foot being adapted to be hinged tio-.an artificial leg1 body, said foot beingY provided with a'soclret for a Spring, sunk through the upper body thereof to the said rniiting strip, substantially as described.

S. A11 artificial fool' comprising a sole body, an upper body, and an interposed uniting tonp'ue ot relatively hard and tenacious-'iina-teria an elastic strip extending upon the foot, said strip beingA rigidly secured at one end to said sole bolt, extending .througli said foot and through the said tongue. of hard material therein, engaging-the otherwise free end of said'elastio strip, andai-'bile securing the component parts Iof said foot serving also to hold tense said elastic strip, substantially as described.

'9. An arti'licial foot comprising ,a plurality ot' built up parte and a. bolt extending through and uniting said parts, said bolt consisting of a sleeve extending through a .hole in Ithe toot formed to receive it, an langular head upon said sleeve engaging a correspondingly shapedrecess in the surface oisaid foot, ,a Sergeii1 thread formed upon the inner surface of said sleeve, and a screw entering the hole Vthrough said foot oppositeio the head' formed upon the said sleeve and engaging the internal thread of Said sleeve, substantially as described.

In testimony whereof, l have hereunto set my hand.

ENGELBERT MU ELLER. W it-nesses: i

CHARLES BArNErfr, FRANCIS J. Terrasson.

ody, and a roo 

